prepare to register ec shard info in master

weed/topology/topology_ec.go

@@ -0,0 +1,43 @@
+package topology
+
+import (
+	"sort"
+
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/pb/master_pb"
+	"github.com/chrislusf/seaweedfs/weed/storage/erasure_coding"
+	"github.com/chrislusf/seaweedfs/weed/storage/needle"
+)
+
+
+func (t *Topology) SyncDataNodeEcShards(shardInfos []*master_pb.VolumeEcShardInformationMessage, dn *DataNode) (newShards, deletedShards []*erasure_coding.EcVolumeInfo) {
+	// convert into in memory struct storage.VolumeInfo
+	var shards []*erasure_coding.EcVolumeInfo
+	sort.Slice(shardInfos, func(i, j int) bool {
+		return shardInfos[i].Id < shardInfos[j].Id
+	})
+	var prevVolumeId uint32
+	var ecVolumeInfo *erasure_coding.EcVolumeInfo
+	for _, shardInfo := range shardInfos {
+		if shardInfo.Id != prevVolumeId {
+			ecVolumeInfo = erasure_coding.NewEcVolumeInfo(shardInfo.Collection, needle.VolumeId(shardInfo.Id))
+			shards = append(shards, ecVolumeInfo)
+		}
+		ecVolumeInfo.AddShardId(erasure_coding.ShardId(shardInfo.EcIndex))
+	}
+	// find out the delta volumes
+	newShards, deletedShards = dn.UpdateEcShards(shards)
+	for _, v := range newShards {
+		t.RegisterEcShards(v, dn)
+	}
+	for _, v := range deletedShards {
+		t.UnRegisterEcShards(v, dn)
+	}
+	return
+}
+
+func (t *Topology) RegisterEcShards(ecShardInfos *erasure_coding.EcVolumeInfo, dn *DataNode) {
+}
+func (t *Topology) UnRegisterEcShards(ecShardInfos *erasure_coding.EcVolumeInfo, dn *DataNode) {
+	glog.Infof("removing ec shard info:%+v", ecShardInfos)
+}